This invention relates generally to the art of hot-water house furnaces (furnaces using hot-water radiators for heat distribution) and more particularly to a device for increasing the water capacities of such furnaces and for making such furnaces more efficient.
A number of U.S. patents have been obtained for devices which capture waste heat from furnaces in order to increase efficiency, some of which are U.S. Pat. No. 4,467,959 to Laviguer, U.S. Pat. No. 4,484,564 to Erickson, U.S. Pat. No. 4,485,746 to Erlandsson, U.S. Pat. No. 4,512,288 to Michaud, U.S. Pat. No. 4,557,202 to Warner, and U.S. Pat. No. 4,557,220 to Jannemann et al. However, in most of these cases the structures for obtaining such increased efficiency are quite difficult to add to exisiting systems, many of which require special supporting frameworks and furnace modifications in order to provide sufficient space and support therefor. Thus, it is an object of this invention to provide a hot-water-furnace supplemental water heater which captures waste heat but which also is easy to install and requires relatively little modification of an existing water-heating-furnace system.
In addition, most prior art devices for capturing waste heat from furnaces require special, expensive, heat exchangers. It is therefore another object of this invention to provide a device for capturing waste heat which does not involve the use of special expensive, or delicate, heat exchangers.
Still another shortcoming of some prior art waste-heat-capturing systems is that they often do not increase the water capacity of a hot-water furnace system. It is an object of this invention to provide a supplemental water heater, a system for the supplemental water heater's use, and a method for using the supplemental water heater which increases the quantity of water for holding more heat at a lower temperature than is otherwise possible.